I'll try with a few comments after reading your post:
The governor is self contained and has it's own butterfly that could be broken and not opening or closing quickly when you try to throttle up.
If the Beam part does not have a hose connected to it, it is not being used as a mixer. Must have been from something previously used.
The rod on the carb is to adjust the fuel mixture. The valve that allows the propane to enter the carb must match how far the butterfly is open to make it run right. Try adjusting that to open the valve more compared to where the butterfly is position.