Is it possible to get an extra input on the 08M2 project board by connecting to pin 5 as is possible with the old motor driver board? That would give the option of two inputs and four outputs.
I haven't seen an actual PCB, but the "8 pin Project Board" (CHI040) appears to have a 10k Pull-down resistor and Pads/Terminals already connected to Leg 4 (C.3) and to Leg 2 (C.5). Circuit diagram on page 4 of the PDF.
Do you know if there are any pre assembled boards available, either from the Picaxe store or elsewhere that would run the 08m2 chip? The Axe 023 motor controller board is an example of this but it is no longer available.