As Bob_Sack posted in the bugs thread, Compressors from Galacticraft crashed the client upon right clicking them. With the new version, they not only crash the client, but also cause the server to crash on startup. I have therefore disabled Galacticraft until the next version of WolfPack where we have updated Galacticraft to a version that hopefully has fixed that issue.
I hope this does not cause any inconveniences. However if it does, write to me and I'll re-add the lost items for you once we have it fixed or give the materials used to make them to you.