I can download from the radio, but when I try and upload it errors out. I'm using the daily build from Feb 27th. The log should show a successful download, followed by two upload attempts.

Hmm, that is kinda strange. The result of the upload attempt looks like there is zero communication with the radio.

Silly question: You are pushing the button on the radio to put it into RX mode _and_then_ clicking the OK button on CHIRP to initiate the upload, right? The radio has to be "good and ready" before chirp starts the upload and so it needs to be not just in the clone menu, but in clone receive mode well in advance of CHIRP starting anything.