[whpalmer4]

Well, I just booted up 10.7.4 and it worked without a hitch. On the off chance that the issue is you're somehow not getting the configuration string correct, I've attached a small Applescript which will kill OmniGraffle and configure the new option. Make sure you've saved any work in OmniGraffle, because it won't ask if you want to save changed files! After downloading the linked file, double-click on it to unzip, then double-click the resulting "Enable new OG line mode.scpt" file to launch the AppleScript Editor. Click the Run button, then try OmniGraffle again. If it still isn't working at that point, I'd say your best bet is to call up the Omni support ninjas on Tuesday and have them figure it out: 800-315-6664 or +1-206-523-4152.