I need tech support, please help!!!

I'll try, but I'm no expert.  The 87% complete even though you've finished the course is a known bug.  What happens is some of the problems have been deleted, but the percentage is figured on the original number of problems.  You aren't the first to complain about it.  As to the rest of your questions, I'd say forget about either "adaptive" or "sequential" and just study  whatever courses strike your fancy.  Much easier.  The introductory  and intermediate tactics courses are especially recommended.  They have helped a lot of folks to improve.  For more hints on how to best utilize chess mentor, you might want to do a search of the forum archives and check out some earlier posts.  Also realize that unless you're a genius, any course you study will need to be reviewed.  I'm not the brightest bulb on the tree, so some of these course I've done well over a dozen times and I still have trouble 100%ing them.   While you have your "trial" membership, I'd heartily recommend checking out some videos as well.  Especially recommended are IM Danny Rensch's Live Sessions.  Have fun.

Well the major "bug" that I've noticed is that clicking on the small and big START TRAINING icons seem to load two completely different set of problems.

The large icon gives you a lot of random and uncontrollable lessons, while the smaller icon seems to follow whatever you customize.  But they keep track of your progress separately, and seem to interfere with each other at times to create more bugs.

Thanks for trying to help...  I'd be much more inclined to sign up for a membership if there was tech support and help staff here...