There is light at the end of the tunnel. You may use the SET command to produce larger environment variables.
So rather than unREMarking the SET DELDIR= line you could use the following:
SET DELDIR=C:\DELETE,512;D:\DELETE,512;E:\DELETE,512;F:\DELETE,512;G:\DELETE,512;H:\DELETE,512;M:\DELETE,512;N:\DELETE,512;
SET DELDIR=%DELDIR%O:\DELETE,512;Q:\DELETE,512;S:\DELETE,512;Z:\DELETE,512;
Similarly for the PATH= line you could add SET PATH=%PATH% line(s) as follows:
PATH=H:\OS2\MDOS;H:\OS2;H:\;H:\OS2\MDOS\WINOS2;H:\TCPIP\DOS\BIN;H:\SYS\MDOS\BIN;
SET PATH=%PATH%E:\WIM\STUDIE\MDOS;G:\ENVIRON;
I have SHELL=H:\OS2\MDOS\COMMAND.COM H:\OS2\MDOS /E:1024 in my CONFIG.SYS.