Help programming WP 34s

[merlin04]

I'm trying to program an HP 30b to be a WP 34s, but I'm encountering problems. I've successfully erased the calculator (at least I think I have, the device doesn't display anything when I turn it on anymore) but I'm stuck on the programming part. I've tried both MySamBa and the flash tool in the SourceForge page on both Windows 7 and Windows 10 with a variety of compatibility settings, but a few seconds after I click the flash button, both say something along the lines of "error connecting." I'm using a CP2104 USB to Serial adapter, and I'm powering the calculator off of the 3.3v pin. I've tried connecting the wires by holding them on the pads (with and without the case closed) as well as by using a custom pogo pin board I made.

Any idea how I can fix this?