I am using ProjectRed in the latest version of the Attack of the B-Team mod pack (v1.0.12a). This pack is based on Minecraft v1.6.4 and is using what looks like the latest ProjectRed version (4.3.7 build 32, http://projectredwiki.com/wiki/Version_archive) for this version of Minecraft.

The crafting chips, pipes and upgrades work perfectly if you only have one crafting chip attached to a single pipe network. Once you attach a second crafting pipe to the network and attempt to request an item that needs to be crafted, the game crashes and the application closes. I tried using both cyclic assemblers from thermal expansion as well as liquicrafters from mfr.

There is a thread on the Attack of the B-Team forum (http://forums.technicpack.net/tracker/issue-1847-project-red-transportation-crafting-pipes/) as well around this issue. It appears that at least four different people (including myself) have been able to reliably duplicate this issue.

The crash report is here, http://pastebin.com/vYDWc8Vn

See #447, this is fixed for 1.7 but will not be backported.

Thanks for the quick reply. It's too bad it will not be fixed in 1.6.4 but I understand maintaining multiple versions of code is a serious undertaking. I'll close this issue off and thanks again for the info.