Continuous Orthogonal Polylines
Maybe it will only give you a starting point [for instance, it doesn't Trim the Polyline], but take a look at PLineFilletAlong.lsp with its PLFA command, >here<. It also doesn't have the other capabilities [Splines, etc.] of your referenced App, but given your thread Title, maybe this is all you need.
Kent Cooper, AIA 
@Anonymous wrote:
.... What i was really hoping for was something where i could click on the start point and end point and it would work out the best orthogonal route between the two points. ....
That's pretty wide-open.... You would need to come up with some criteria. Which route is the "best" orthogonal one on the left, if it can be two-legged? If it has to be three-legged to miss something, which route on the right is "best"?
How would it know what it has to work around, if anything? User selection of potentially interfering elements, somehow? It would need to determine their size -- how far away from them should the path stay? Would it be allowable to go in a direction initially more like "away" from the target if that works better around something, and how would it be able to determine that?
Etc., etc.
I kind of have a feeling you could do a heck of a lot of these making those determinations by eye [which your brain can do very easily] in a lot less time than it would take for someone to work out how to instruct a routine to handle all the possibilities.
Kent Cooper, AIA