Hi,
I tend to think manuals are the biggest problem.
If they included a Workshop ( for want of a better word) in the form of a video or DVD it might help.
Years back the local store used to pay me to do one on one sessions with new ( mainly )korg workstation/arranger owners, ie to go through the workings of the board..
It worked out better for the store , to have me spend an hour with a customer( that hadn't used this type of equipment before) than for the keyboard salesman to get tied up with trying to answer questions over the phone.

In most cases that one hour or so, was enough to get them up and running. I also spent time in going thru the manual with them, and marking the spots that were of importance to them ie recording on the sequencer etc etc, so that if they couldn't remember how to do it exactly, they'd just look it up in the manual to refresh their memory.
I'd give them my ph. no. if they got totally stuck, or if they wanted to spend extra time going into more depth, they'd pay me themselves.
Most knew what it was they wanted to do with their boards, just didn't have the time to spend, reading the first 50 pages of a manual just to learn how to switch the darn things on.

best wishes
Rikki