Latest update.. I've got it working!
I'd tested and re-tested with no luck, assuming the Tiny Leo was broken in some way. Just to be sure I found a simple sketch to test the Tx and Rx pins between 2 Arduino boards, everything worked perfectly so I knew the Tiny was ok.
I was watching some Youtube clips on Arduinos and thought I'd punch in a few keywords specific to the Tiny and lo and behold, a Youtuber named SuperEvenSteven has a video using the exact components with Gimx, really well explained.. long story short, the Tiny has to be reset by grounding 2 very small unlabeled pads, just as the firmware is about to load. Tihis puts it into programming mode and the FW loads successfully.
All credit must go to SuperEvenSteven, here is the link to his video:
https://www.youtube.com/watch?v=DsjQWHu ... EvenSteven
Hope this helps someone else down the track.
Duinotech Leonardo Tiny
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