A few moments after leaving the rftools dimension (chunkloaded by MFR chunkloader), the game crashed with the following crash report: http://pastebin.com/YFfM2C5y.
AE version: rv3 beta 4

@fnuecke any idea?

Hmm, the only thing that can cause an NPE at that location is the node's network, and for that to be null after the preceeding joinOrCreateNetwork call on the part's tile entity, that tile entity would have to be invalid. Assuming I didn't overlook anything and my logic holds up, that would mean updateConnections gets called for an invalid tile entity, which is probably not a good thing in general? The quick fix that's highly unlikely to break anything is to add a && this.node.network() != null to the preceeding if.