At today date, the "new" GRBL has reduced these differences, up to the point that although there is still some ones, it no longer makes sense still stuck in v0.9 vs the new features and more compatibility with others third party applications.
It is the free, open source and still in continuous development, so i reccomend to use this one for control the 3dpBurner instead the "old" 3dpBurner Sender and 3dpBurner Image2Gcode. After some tests you will find a simple and very powerfull software.
If you don't use it yet, I highly recommend to take a few minutes and read the full USAGE on his website, test and explore its features. Its a nice work.
How to upgrade to GRBL 1.x
Easy way (using LaserGRBL):
-Make sure you can connect to the machine, then disconnect.
-Go to "Tools" menu and "Flash Grbl Firmware".
-Select Arduino UNO as target and the latest GRBL version (Original, not the XY Homing one).
-Click OK and wait.
After finished, it is recommended to connect to machine and type $RST=* on the manual command text box and press Enter (this will wipe the GRBL EEPROM values).
Then go to "File/Open File" and load this configuration file, then press the Run button, this will execute the file and set the 3dpBurner parameters into GRBL EEPROM, if you get any error repeat the configuration process until 0 errors.
If you need to fine tune any parameter, like maximun axis rate or acceleration you can go to "Grbl" menu and click "Grbl Configuration". Modify your values and press "Write."
I created some custom buttons for laserGRBL, check downloads page.