Working on the front end of the car, heated & scraped out all cracked or questionable seam sealer from the front wheel wells and trunk. Did all the requisite prep work and applied the new 3M brushable seam sealer yesterday. Was supposed to be painting today, but the spots where I had to build up the sealer are skinned over but still soft below the surface. No directions on the can and 3M's tech site basically says work fast and that's it. No info on aiding curing or problems with high build spots etc...This stuff appears to be a popular seller, but I thought it applied horribly. It is not truly brushable and skins so quickly you really can't tool it. Anyhow, I'm reluctant to move on and paint over this stuff because it seems like when it does eventually dry out it will probably shrink and crack, and ruin whatever I paint over it. This stuff is definately no substitute for the factory sealer, but I can't afford $175 for the Wurth applicator gun just to redo a few spots. Tried some light heat gunning but it did not help.
Anyone out there had any similar experience with this crap? What can I expect to happen? Do I need to wait a week or so for this stuff to cure before it's safe for me to paint?

Im not sure about the curing time, but as far as application goes, it may be faster and alot more precise if you use your finger to apply it. Thats how I do it and it seems theres more precision and less mess.

I has some of the 3M stuff shrink and then crack as you would expect. I didn't paint over it until I was sure it had cured, etc. so that I didn't tray any volatiles in it. I had some other brand that was easier to apply, but I don't remember the name. It was whatever the paint store sold.