Try to replace the new startup.rphs file with the one from previous version. You'll have to load LSPDFR manually again (press F4 then type loadplugin "LSPD First Response.dll") but this way you will be able to toggle between lights and siren.
Hi Brendan,
I figured out what's causing the crash. If you delete the following plugin: VIPPU 0.9.2.1 you should be able to call in a pursuit (ALT + E) without any crashes.
Let me know if it worked out. Good luck.