My Movies does support serial control for powering on and loading a given changer slot. The screenshots below are from the Collection Management application for My Movies 4.04 (Build 4) and pretty much speak for themselves. Couldn't be easier to setup and use. Also, I've remained on My Movies 4, because with My Movies 5 you are no longer able to export your local database (profile data and cover images), then importing it to their mobile app. And the big one, the synchronization model is mandatory and on steroids with My Movies 5 and blows. I have no interest in the Collection Management application being tied at the hip with their online servers, but I digress.

Tools->Disc Changers:


Tools->Disc Changers->Configure Disc Changers:




Title->General Profile Data->Discs->Assign Discs:


The one issue I have with the changer support is that when selecting a disc from My Movies for WMC7 (either directly or by way of the mobile app) and choosing "Play" the changer plugin will send the command to power on the changer, then request and wait for confirmation from the changer that it's powered on before sending the command to play the disc.

Unfortunately what can happen is that if My Movies doesn't get an answer back from the changer that it's powered on after a certain period of time an error message will be displayed and the sending of the command to play the disc is aborted. And here's the thing, to date I have yet to see My Movies not power on the given changer. Sometimes it just takes longer for the changer to power on and I assume then be able to receive and answer back that it's powered on per the command being sent to play the disc. My Movies will also from time to time state it can't open the com port. Happens rarely for me, but happens nonetheless. That error will happen the moment you attempt to play a disc and requires a restart of the HTPC in most cases.

Be that as it may, the main benefit of My Movies for me is the ability to browse my Blu-ray collection using My Movies for WMC7. Being able to initiate playback of a given disc within the interface is just the icing on the cake. That being said, even if I do use My Movies for WMC7 to initiate playback of a disc, I'm still then changing to the particular changer activity with my Pronto. As such, I'll pre-select the changer slot anyway with my Pronto prior to going to the changer activity. (See my prior post.) Makes no sense not to. If My Movies ends up failing to play the disc I've already got the changer slot pre-selected once getting to the changer activity and can just send the command myself with a press and hold of the "Ok" hard button. In fact, even if I don't need to I'll send the command anyway that way the value is stored in my Pronto as I'm tracking the last disc played for each of my changers now.

Many thanks for the info,top!! . Was working with my movies 5!! , now i have problems with loading my movies 4.07 , it says all the time that is not finding connection to the database or some change is made to my account ?? so i have to find out what the problem is with that .Now i have to find a serial cabble with 2 female connectors for connecting the player to the shuttle htpc ,have loads of male-female versions .I hoped that it could work via network connection. let you know the progress

There is an issue with the My Movies 4 installation packages with respects to SQL which is not going to be addressed. That being said, I've been able to roll back from My Movies 5 to My Movies 4 successfully. I've also been able to roll back from My Movies 4.07 to My Movies 4.04. Posted the below over at the My Movies forums outlining the steps required. Enjoy!
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I completely wiped out my Windows 7 64-bit installation of My Movies and SQL not too long ago and was able to successfully install My Movies 4 which uses SQL 2005. The steps I took are outlined below.

1. Uninstall My Movies from Programs and Features.
2. Uninstall all instances of SQL from Programs and Features.
3. Run the My Movies Clean Tool found here.
4. Delete any My Movies and SQL directories left behind.
5. Download Microsoft SQL Server 2005 Express Edition (SQLEXPR.EXE) and rename the file, "SQLEXPR32.EXE".

(When attempting to install My Movies 4 prior to this SQL would fail to download and install. Checking the "C:\ProgramData\MyMovies" directory created by the installer I found a file 0kb in size named, "SQLEXPR32.EXE".)

6. Run the My Movies 4 installation file. When prompted to select the type of installation first place the "SQLEXPR32.EXE" file in the "C:\ProgramData\MyMovies" directory the installer created.
7. Select the type of installation (stand-alone in my case) and next. The installer should then show that it's attempting to install SQL, a separate dialog box being displayed asking if it can run the "SQLEXPR32.EXE" file. Select the option to run the file.
8. After a time you should receive another separate dialog box asking if you're sure you want to install SQL and that if you do "Microsoft SQL Server 2005 Service Pack 3" should be installed afterwards. I selected the option to continue with the SQL installation. (I did not find the service pack was required.)
9. After a few minutes the My Movies installer should notify you that the required components for My Movies have been installed, the option then given to install the actual My Movies application.
10. Continue with the My Movies installation at that point which should complete successfully.
11. Once installed launch the Collection Management application which should connect to the My Movies database instance without issue prompting you to log in to your account.

have set everything up last night after finding the right serial cabble, running again on my movies 5 and loaded about 300 blu rays over night ,so far i have tested to control the bdp and so far no problem with it . player starts up when it is off and get the right movie in the slot everytime i tried , only have to swith the Yamaha dsp-z11 with the Pronto to the right HDMI input and back again for choosing an other movie.
so that works great!! so far

wil test it for a longer time now to see if it keeps ok

so now i have to set up the remote app on the mobile version so i can have cotrol from the I-Pad

thanks for the info for how to load my movies 4 , have to see if 5 wil work for a longer time without troubles

Great to hear you got it up and running and yes, the changer support continues with My Movies 5, so if that's your pleasure by all means.

And keep this in mind as well, to initiate playback from the mobile apps you'll still need to have My Movies for Windows Media Center actively running. Would be great if that wasn't the case, but unfortunately it is.