Disapperaing Dimension Lines

I have been having trouble with the Insert Model Items command.

Sometimes when I insert dimensions from the model I want to reposition them to clean the drawing up a bit. However, sometimes when the dimension gets dragged to a certain point, the extension lines disappear.It is getting increasingly frustrating,especially with this drawing because Solidworks (unlike Solid Edge) does not (as far as I can tell) have an angular dimensioning option where you can select an angled line and it dimensions the angle from horizontal/vertical from the endpoint of the line. So when I import model items, the dimension is coming in how I want it to look, just not in the right position.

I guess I am combining to questions/problems here. First thing first: How can I fix the disappearing extension line problem?

Secondly: Angular dimensions require a second reference line, which may not be available. In order to get the dimension correct I have to draw in a miniscule vertical/horizontal line to dimension off of.

Help with either (preferably both!) of these problems would be greatly appreciated!

Thanks,

-Keith

SolidworksDrawings And Detailing