This handy little tool will allow you to quickly switch between two skins. Freeway is forcibly closed in the process, so playback will be stopped.
+Unzip and place "Freeway Skin Swap.exe" in your Freeway Ultra folder.
+Add the highlighted tags to your freeway.ini file:
[Global]+Run "Freeway Skin Swap.exe" whenever you want to switch skins
Source code is tiny so I will post it here if anyone wants it:
; Freeway Skin Swap.ahk
; AutoHotkey Version: 1.x
; Language: English
; Platform: Win9x/NT
; Author: unlfrank
Process, close, FreewayUltra.exe
Process, close, mplayer.exe
IniRead, AltSkinVar, freeway.ini, Global, AltSkin
IniRead, SkinVar, freeway.ini, Global, Skin
IniWrite, %AltSkinVar%, freeway.ini, Global, Skin
IniWrite, %SkinVar%, freeway.ini, Global, AltSkin