I found two serious bugs in 2.6.22f4. The first one is that UModeler object is snapped even though Grid Enabled is off in the settings. The other is that Pivot Tool and Pivot To Center Tool don't work as expected like UModeler object jumps as soon as applying a new pivot.
Now these bugs have been fixed in 2.6.23. In addition to it assigning a material to a whole object using shortcuts have been implemented.
The change log is as follows.
Fix : Fixed not disabling grid snapping in Object Mode.
Fix : Fixed object world position jumping when using pivot tools.
Enhancement : Enabled a material to be assigned to a whole UModeler object in Object mode using a hotkey.