Can we fix NSIS?

appveyor.yml

@@ -24,7 +24,6 @@ install:
     # Replace makensis.exe and files with special long string build. This should
     # prevent issues when setting PATH during installation.
     - 7z e "tools\nsis-3.05-strlen_8192.zip" -o"C:\Program Files (x86)\NSIS\" -y
-    - 7z e "tools\EnVar_plugin.zip" -o"C:\Program Files (x86)\NSIS\" -y
     - build_win all
     - refreshenv
     # We need to reload vcvars after refreshing

janet-installer.nsi

@@ -1,6 +1,7 @@
 Unicode True
 
 !echo "Program Files: ${PROGRAMFILES}"
+!addplugindir "tools\"
 
 # Version
 !define PRODUCT_VERSION "${VERSION}.0"