UN-Trixing Trixbox

I have used the procedure described in the Wiki using Module versionupgrade-2.4.0.1.tgz to upgrade Trixbox 2.6.1.13 with FreePBX 2.4 to FreePBX 2.6 and then to 2.7. I now have the traditional Blue FreePBX interface with the Trixbox Logo and the green [System Status Packages PBX System Settings Help] bar above FreePBX.

Everything appears to be working normally except when Submitting Changes in some modules the orange bar and FreePBX page do not re-appear below the Trixbox Logo and task bar, the page is just blank.

I see this behavior with the Trunks and Outbound Routes Modules while the Extensions, Feature codes and Custom contexts Modules are behaving normally. That is as far as I have gone at the moment, there may be others I have not discovered yet.

It seems to me that this is most likely resulting from the tweeks made by Fonality when de-FreePBXing Trixbox. Can anyone make any suggestions how I might fix this problem? Any help will be gratefully appreciated.

I should add that the way out of this is to select PBX/PBX settings from the Trixbox task bar. The FreePBX System status page appears complete with orange bar. Clicking the orange bar completes the operation as normal.