Took me a week to program a theater room with an MC2W and mt-1000. Just nights after regular hours. I went to essentials about a week later. Figured out some better ways to do things. I have a very week programming background.

I'd say 20 hours is enough time to get the basics down and program single room systems. Downloading example programs from Crestron and reverse engineering is a decent way. Dissecting them. Helped a ton.

Make friends with a CAIP and having them there to help with questions, will make you more confident in selling the product