Editor crashes when selecting static mesh

Hey! i upgraded my project to 4.9 last night and i have run into a myriad of problems but the most important one right now is that my editor completely crashes when i select a static mesh in my scene, no idea why but its causing a bit of grief.

heres my crash report:

MachineId:3658AD0745543FD7E0528A81B5692668
EpicAccountId:c9fa38c11212415abd5a7e8cd2c8f56f

No minidump found for this crash.

thanks!

My whole editor seems to crash if i add a transluscent material to anything, pretty frustrating :confused:

I have narrowed the crash down to having “dynamic indirect lighting” ticked on my directional light, was hoping to use GI for this project and it was looking alright when i was using 4.8, guess i should figure something else out huh?