[REG2.066a] Issue 12399 & 12400 - fix name lookup and diagnostic issues

[Issue 12399](https://d.puremagic.com/issues/show_bug.cgi?id=12399) - Static and selective import acts like a normal import
[Issue 12400](https://d.puremagic.com/issues/show_bug.cgi?id=12400) - Misleading/useless diagnostic on bad fully-qualified symbol name