Thanks Sunka, that seems to initially work in the Test your BBCode area, but in an actual post I get the "Wrong map URL, edit the post to change it. Reload the page when finished to check if correct." error message.
On return to the BBCode Manager, and trying the Test your BBCode again, I also get the error there as well.
This is the sample map code used in all instances;
Also in the BBCode Manager window, the "Example" field doesn't work, as the code above gets trimmed when saved... and looks like this;
Code:
[gmap]<iframe width="425" height="350" frameborder="0" scrolling="no" marginheight="0" marginwidth="0" src="[URL]http://maps.google.com/?ie=UTF8&ll=26.468114,-80.065699&spn=0.024625,0.028195&a
Any further thoughts?