After 500+ hours of KSP and lots of trial and error, I finally managed to build a space shuttle that not only goes to space, but is actually glides well and doesn't try to fly backwards like my planes usually do.
I launched it many times using the simulator and it worked perfectly! When I did my first real launch, the external tank didn't separate correctly and got stuck to the orbiter, my guess because it was attached to a cargo bay. I tried to go to space center and switch back to the ship to see if the tank would then detach. Well, technically it worked, it blew the whole thing to smithereens and now, instead of one big problem, I have 84 small problems
Time for a rescue mission.