I got stuck at a part in DKS in my dragon form at a part where I had to fight some boss character — apparently I neglected to upgrade the dragon adequately. I don't have the energy to go to an earlier save and haven't found any cheats that will work without crashing the game. But I really have enjoyed what I have played of it.
I don't think it is even possible to screw up to the point you can't advance in the game [at least in the mentioned dragon category]. Even if you tried your very hardest it should be nearly impossible due to the limited options you have for dragon skill upgrades.
Or are you missing the armor pieces? They do have nice stat boosts but they aren't really vital as far as I can remember.
Also, as far as I remember you can redeem all of your skill points including the dragon skill points at least once for free at just about any time in the game. If you are playing DKS you are getting at least one totally free full respec (I believe it was even more freebies though), i.e. you can redeem all of your skill points and spend them all on a totally new build.
After the free respec(s) you can always buy another respec with gold (at the Battle Tower) and as long as you don't overdo it, it is pretty cheap. Even if you play quite casually you should easily be able to afford at least two or three respecs.
So there is no need at all to go back to a previous save. Just hit the trainer and change your skill set to something more effective, i.e. give your dragon form a good mix of offensive and defensive capabilities (and a good dose of healing).
Finally, I don't really remember a part except for the very final mission of DKS (i.e. the end of the FoV add-on) where you needed to defeat a boss in dragon form to advance. The final mission can be a bit tricky unless you know how it's done and how to use your tools/weapons properly. Took me some time (and forum reading) to figure it out as well.
It was almost a bit unfair since the add-on has so little dragon form gameplay and then you get tossed into the middle of a fairly hectic escort mission (which I dislike anyway due to the usually stupid suicidal AI on escorts) for the grande finale but it is definitely very doable once you know how (YouTube vids might also serve as a good source of inspiration if you have problems finishing that part of the game).
In short: Just fucking do it!
