Woops. The invalid version number was my fault; I screwed up the semantic versioning. I released a new version yesterday which is identical except for the version number which is now a valid 0.28.3.
But that isn’t actually your problem. The invalid version number and the stuff about “requestFrom…” are just warnings. It compiled anyway. The real problem is that it didn’t find your Mayfly at your selected COM3. Are you sure the Mayfly is actually connected, powered on, and enumerated as COM3? Sometimes after a reset Windows will decide that the same Mayfly is a new device and will assign it a new serial port with a higher number.