Okay. Here's what I would suggest. Change to 4-wire and leave the other settings the way they are. For wire is easier to troubleshoot. Now, once you're set up for 4 wire, the PBX vendor may tell you that you only need six wires
E, M, T, R, T1, R1
In type I SG and SB are not used, however, the router needs that ground so it recognizes 0 VDC. Have the PBX vendor wire all leads to a 66 block and label them. E,M,T,R,T1,R1,SG. If he has no SG lead do to it being type I, leave an open pin for it anyway. On the four SG pins, daisy chain a wire between them and run it to a ground (there will be a ground post on the PBX chasis. If you can't find it, any old thing at ground potential will do, ie outlet gnd). Have some cat5 cable and four rj45 jacks handy. I only say cat5 because there's 8 wires in it. Punch down the jacks and put straight thru patch cables between them and the router ports. The only open place you ahould have at this point is on the router side of the 66 block for you to punch down the leads of the cat5.
If you have visio, I will gladly send you the diagram I did up to guide you thru the last part. If not, I can send it to you as a screenshot.
The only problems you may run into after all this is human error, or T+R and T1+R1 may be crossed due to labelling error. In any case, if you can get that far the rest is all down hill.
P.S. Troubleshooting tools to have whenever doing E&M are a volt meter and a buttset. Thats all you need. [sig][/sig]