Just trying to get Builder 2 set up to test it but fell at first hurdle.
CF 9 on Windows 7.
Basically I added workspace and project and a localserver, then I added a test page, but somethings messed up because I cannot preview the test page in Builder 2.
If I open an external browser at the test page http://localhost:8500/testproject/test.cfm it works fine, and hovering over the firefox and IE tabs in Builder 2 shows the same address, but in IE (9.08 64 bit) I get "This program cannot display the webpage" error.
Hmm no unpaid support for trial users, and no forum support = no purchase I think.
I can't vouch for CFB... indeed for whether this is still the case now that CF is an Adobe product rather than Macromedia, but Macromedia used to offer free support for installation issues for ColdFusion. It might be worth checking if Adobe offer the same with CFB.
As for your specific problem: I never use the built-in preview stuff, I just use an external browser, so have no idea what the story might be, sorry.