Failed to start a pvp game with Vehicle turrents 0.1.10 and Factorio 0.16.51
Here is the error output:

Error while running event level::on_gui_click (ID 1)
Error while running event Vehicle-turrets::on_research_finished (ID 18)
__Vehicle-turrets__/turrets.lua:236: attempt to compare nil with number
stack traceback:
    .../AppData/Roaming/Factorio/temp/currently-playing/pvp.lua:2338: in function 'setup_research'
    .../AppData/Roaming/Factorio/temp/currently-playing/pvp.lua:1696: in function 'setup_teams'
    .../AppData/Roaming/Factorio/temp/currently-playing/pvp.lua:391: in function 'prepare_next_round'
    .../AppData/Roaming/Factorio/temp/currently-playing/pvp.lua:1023: in function 'config_confirm'
    .../AppData/Roaming/Factorio/temp/currently-playing/pvp.lua:2621: in function 'button_function'
    .../AppData/Roaming/Factorio/temp/currently-playing/pvp.lua:3585: in function 'on_gui_click'
    ...Data/Roaming/Factorio/temp/currently-playing/control.lua:45: in function <...Data/Roaming/Factorio/temp/currently-playing/control.lua:44>

Thanks a lot for letting me know and giving me the error output =)
Pvp games can be created now, but there seems to be some weird things happening with research when creating pvp games, which causes the research for increasing max turrets to trigger on start.
This means that the maximum amount of turrets on a vehicle is maxxed from the beginning. The other research still seems to work as intended.
It's limited how much I can test pvp, as I am just one person, so please let me know if you try it out and encounter other bugs