* I see an option to Import Tests under the Tests tool. Can I upload a Word document here?

Not quite.  Blackboard lets you import files of questions, but only if you format the questions in a specific way.  You will most likely find that creating questions one by one will be easier.

* My students are having trouble taking my online test. Why is this and what should I tell them?

Using an uncertified browser, losing an internet connection or starting a test and then using the back arrow to back out of it are some of the many triggers that cause problems with Blackboard tests.  Many instructors give a low stakes practice quiz so that students who have never taken a Blackboard test get a chance to ‘mess up’ once.