These scripts by bman were designed to give any user access to run 2xZdoom without the need to manipulate any command line parameters.
Release notes:
Put the main iwad files into the ./wad directory. Put the pwad files (and any associated content i.e. wadname.deh) into the respective subdirectory.
Run Zdoom_selector.gpe.
Select your desired run level (original, new iwad, pwad/dehack) with A/Y, select your wad (none.wad is included for original games because selector needs an input file) and hit Ztart. It may take several seconds to start.
To warp to a particular level you can include wadname.warp with the selected map level (see zdoom.txt from 2xZdoom). This is actually required for heretic and some doom pwads.You can locate warp level data in text that accompanies a modified wad.