I just published a new gcodeprintr beta version (v1.62).
It fixes a major bug in the printer communication code when using printer electronics with FTDI serial chip. Due to the bug the last 2 bytes of a 64byte usb paket were lost (causing odd behavior and timeouts).
Other changes are
open gcodes from email attachment
extrusion speed option
autosave baud rate when detected
Removed M114 Gcode when doing manual moves (executed only on debug)
To participate in the beta you need to be member of this community and then opt-in here:
https://play.google.com/apps/testing/de.dietzm.gcodesimulatorprinter