So apparently, DaTuner does not work on HTC G2 (Magic) and I don’t have one to test with. Finally, somebody has contacted me who has this problem so I can start to delve deeper into the problem, assuming that person helps out and can describe the problem in a bit more detail than “it doesn’t work”.
Until then, an old version of DaTuner that should work on G2 can be downloaded from here:
Keep tuned for a fix to the newer version of DaTuner
It took forever to get a second response and when I finally did, he reported that after a reboot it started working again.