There is a bug I keep stumbling across after launching something into orbit, then going back to the VAB The tools and VAB sidebar disappear and reappear, but the part sprites stay.
Image of bug:
http://imgur.com/a/ILYew
Mods:
UKS, ColorCodedCanisters, Firespitter (core), FTP, InterstellarFuelSwitch, RasterPropMonitor, KER, KIS, AVC, InfernalRobotics+rework, MechJeb, MRS, DPAI, NearFutureSolar, Phoenix Industries MAV, PlanetShine, ProceduralFairings, RCS Build Aid, RealChute, Station Science, Tarsier Space Tech, Trajectories, Kerbal Alarm Clock, Tundra Exploration and TweakScale.
Thanks!