Hey,
I know how you feel! I have same problem with trim also with my attack 3 being to sensitive.
Trim, I'm slowly experimenting and im slowly getting used to it. My ka50 goes nuts when i don't touch my stick, so what i do i try and straighten it up and while its straight i press trim button and release it when its fully straighten up, and it seems to do the job, i have to do it often but apparently thats how it suppose to be done.
Regarding your stick being to sensitive i had some problem i solved it by going to options/controls and then when you click AXIS X and tune you can change settings a bit, i made mine have death thing of 20 and the curve thing (i think the last options) being 20 as well. It makes the like a curve a bit and it makes the stick way easier to operate. Make sure you do it for AXIS X and Y.
Maybe someone can tell me how I enter the mode that you are in when you do training. ie. when you have free look AND you can click as well. I can use LALT+C to look around with my mouse, but i have to press it again in order for me to click the buttons inside the cockpit. Any ideas?