Rename the .gm to .fgc or .nc, then you can import the file into TM Cad and it will show up as a line drawing. You will need to delete the lead-in/outs as well as the objects will be slightly bigger or smaller depending on the kerf compensation.
.CDL files just needs to be OUTPUT to become a .GM you can follow the video at https://torchmate.com/university/tmu-2-exporting