I've recently run into this problem as well. When attempting to author an FLA to SWF everything works just fine. However, when loading my newly authored SWF into a larger project I get these errors. Specifically, I'm generating a file called gazette.swf which must support native newsfeed languages from around the world (hence the TLF text fields). This runs both standalone (ctrl-Enter) and in the sandbox (ctrl-shift-Enter) without issue. But when loading. But when its loaded via URLLoader into another project I get a "method is undefined on gazette__Preloader__" ...
The only solution I've found is to set the default linkage to Merge To Code, but I hate programming by cooincidence. The adobe docs don't give us much. Any Adobe moderators out there want to help?
I just found the answer:
Checkout the last section entitled "Publishing SWF files with TLF text"
Long story short, check out your build directory. A SWZ file was created for the SWF with TLF file you just created. Unless you're willing to deploy the auto-generated file called textLayout.X.X.X.X.swz in the same web directory as your SWF file, or allow your code access to Adobe.com, you'd better bundle that TLF library into your SWF by selecting Merged Into Code for the Default Linkage.
Hope this helps