Changed behavior of the entire database selection process. A real "upgrade"/"don't touch the database" option was added, and the old options unconditionally delete the database.
Function BNSetWAMPInstalledFlag
ClearErrors
ReadRegStr $wampstack_installed HKLM "Software\BitNami\BitNami WAMPStack" "Location"
IfErrors 0 +2
StrCpy $wampstack_installed 0
ClearErrors
FunctionEnd
Function BNSetWAPPInstalledFlag
ClearErrors
ReadRegStr $wappstack_installed HKLM "Software\BitNami\BitNami WAPPStack" "Location"
IfErrors 0 +2
StrCpy $wappstack_installed 0
ClearErrors
FunctionEnd