I had my GM5 replaced in march after experiencing the same problems as OP, I had the first Hardware version (HW 01 SW 06) and now have the latest for this model (HW 32 SW 45). One difference I noticed with my old GM5 module compared to the ones I saw on the web was that mine had 4 resistors instead of 2 (separated by a metal wall). I did however had to get it initialized (?) to the car by the Stealer and they didn't even program the old settings back in the new unit..... When I asked why the dude replied: "cause you didn't asked"........
320i Executive Sedan | E46_AV11 | ZF5HP19 S-t | M54B22 | 170hp 210Nm | 09/2000 | 171k | 32.9 MPG
Re-surfaced CH | VC+VCG | CAM/VANOS timing | IMG | NGK-i | BAT+ALT | O2's | GM5 | WP WPP | PSP | DISA | TB ICV MAF | CCV | CAI | OFHG | FP | FF | A/C | FSU | AUC | WSS | BL BD BP | Mango | JFOJ | SB TP IP | springs | Shocks | tires | ASC+ | alignment | E.Flush | Castrol SAF-XJ 75W140 | ZF LGF5 ATF Flush | FCA+FCAB | Struts