How do you replace FileAssociation.nsh

Every time I install a new version of NSIS, FileAssociation.nsh is eliminated.
My install uses that to register an extension.

    ;Register the vis extension
    ${registerExtension} "c:\Program Files\WinShear32 Viewer\WS32viewer.exe" ".vis" "VIS_File"
    ;Assign the icon to vis files.
    WriteRegStr HKCR "WS32viewer.Document\DefaultIcon" "" \
    "$INSTDIR\WS32viewer.exe,1"
    ;Call RefreshShellIcons 

I'm having trouble finding how to do that differently.

Thanks

When you install you are asked if you want to uninstall the old version, don't do that if you want to keep your old files.

The other alternative is to store 3rd-party files somewhere else. I personally have multiple NSIS installs and I keep the 3rd-party stuff somewhere else.

Oh ok, that's what I've been doing. I wasn't sure if I'd run into EoL on that or not.