File manager behaves oddly when opened from messaging app

USED IMAGE:
current build number: 46
device name: krillin
channel: ubuntu-touch/devel-proposed
alias: ubuntu-touch/utopic-proposed
last update: 2014-09-22 09:25:09
version version: 46
version ubuntu: 20140922
version device: 20140919-1b3e670
version custom: krillin-0.6

TEST STEPS:
1, Reboot the device to ensure that this is first time messaging app is used.
2. Open message app
3. Select conversation
4. Press camera icon
5. Select File Manager
6. Slide back to messaging app view showing File Manager icon.
7. Go back to File Manager by choosing the icon.

EXPECTED RESULT:
File manager should open nicely in both step 5 and 7.

ACTUAL RESULT:
In step five user sees briefly directory tree with directory icons before UI settles to directory which is actually opened.
In step 7 I've seen at least 3 outcomes. Most usual outcome is that you see File Manager briefly but it closes itself and
UI return to view showing Gallery, Camera and File Manager icons. Second one is where where File manager looks oddly dim. Third one which I've seen only once was that UI did not react to several pressings of File Manager icon, then the vibrating event was triggered and File Manager opened as in step 5. If I compare to how camera works here, I suspect intention is that if user slides away from file manager it should behave same way as camera does in same situation (i.e close itself) but it is too slow.