Fixed ISCC path normalization by trimming surrounding quotes from ZOITECHAT_ISCC_PATH and storing discovered default paths unquoted (so they can be checked reliably with Exists(...)).
Fixed installer invocation by quoting $(IsccPath) at execution time in the pre-build command, which supports paths like C:\Program Files (x86)\Inno Setup 6\ISCC.exe
Python3Enabled (python executable + import lib + cffi)
PerlEnabled (perl executable + perl runtime DLL + gendef.exe)
InstallerEnabled (Inno Setup iscc.exe).
Updated the Python plugin project to compile only when Python3Enabled is true, and otherwise emit a clear skip message instead of failing prebuild/import steps.
Updated the Perl plugin project similarly to gate build steps on PerlEnabled and print a skip message when prerequisites are missing.
Updated the installer project so it only uses C++ targets when InstallerEnabled is true, with a fallback skip message when Inno Setup is unavailable.
Added a new MSBuild target (ValidateWindowsBuildEnvironment) that runs before build prep and fails fast with explicit errors when GTK/GLib/OpenSSL headers or Python are missing, instead of allowing a long cascade of downstream compile/link/copy failures.
Updated the Windows build to prefer glib-genmarshal executables with a Python fallback for marshal generation.
Made GTK link dependencies more robust by selecting available ATK library names before assembling GTK libs.
