1- Make sure you download latest QFEs applicable to WLK you are using. QFE packages can be found @ Microsoft Connect download page.You can find the instructions @ http://www.microsoft.com/whdc/winlogo/WLK/WLKQFE.mspx
2- Make sure you check my blogpost about the applicable erratas to Mobile Broadband tests. All erratas can be found @ https://winqual.microsoft.com/EC .
3- Make sure you have all the SIMs required for Logo testing. Please see my blogpost about the SIMs required for Logo testing.
4- Make sure that the PIN for your home SIM and roaming SIM are same.
5- Testing with the fastest network available is recommended.
6- Make sure you delete all SMSes on the SIM/Device before running the SMS tests.
7- You can use standalone NDISTest and make sure you can pass all tests before starting the logo pass from DTM. Running NDISTest standalone gives you the flexibility to re-run a particular test or a set of tests without running everything. You can also modify the parameters i.e. APN info, debug output, severity of debug prints, running tests in loop, stop on fail etc. from NDISTest option window. You can also pass custom parameters to the tests (called 'hot parameters') by right clicking on the test name from NDISTest GUI before stating the test run.