I think it is inherently hard (and time consuming) because the appraiser has to learn two new things at once.
When I explain it internally, I tell people that for most appraisers using their forms software is like driving their car to the local grocery store. When you make a quick grocery run, there are hundreds of things that you have to do, but you don't have to think about doing them (e.g., open car door, sit in seat, put on seatbelt, hit button to open garage door, wait for door to open, step on brake, push button to start car, move gearshift to R to back out, etc. etc.) All those little things happen autonomically, because you have done them countless times before. That is the way your software is if you do any volume at all. When I was still in the field I didn't have to think about my forms software. My fingers just automatically went to the right keys and/or mouse clicks.
All that autonomic activity has to be re-trained. And, it has to be re-trained on a completely new format with a new data structure (no more forms, no more GLA, bath count is handled different, etc.) Instead of hopping in your car and driving to the local grocery store, its like you are being dropped into a stick shift, in England, with no GPS, and you are low on gas. Its a lot to take on all at once.
As I have said before, I have set a few of them up as if I was going to use them in my local market. In each case that basically took me a full Saturday to do. I think its fair to say that I started the process with an above average understanding of the 3.6 structure, and it still took me a long time. And, setting up the ones I had used a lot in the past did not go any faster.
Having said that, I think that it is important to invest that time and make a good software selection. If you pick a software that does not fit your specific workflow, you could easily cost yourself extra time on every assignment, and that will extra time will keep adding up as long as you use that software. There are currently 10 verified software providers, and several more on the way. Some of them are far better than others, in my view, and there really is no easy/fast way to determine what is best for you. I think one of the worst things one could do would be to commit to a specific software without even looking at or considering some of the other choices.