Cdsenv setting with Backannotation in LayoutXL

Hi, thanks for your time.

I have a few questions with the 'backannotation' in Layout XL.

1. lxDummyBackAnnotateMFactorName

I want to know what this setting is. 

I found that when I make instances to freeze pcell, make dummies with "create dummy with net" , and wirte "m" to the value of "lxDummyBackAnnotateMFactorName" in the Cdsenv Editor,

then, the dummy instances are insered with mulit factor in Schemaic when the backannotation is executed.

However, if I don't wirte any value of "lxDummyBackAnnotateMFactorName", then instances which is made by freeze pcell in Layout is not inserted with multi factor.

The point is, I want to know that "lxDummyBackAnnotateMFactorName" is only for backannotating the freeze cells with multi factor, or there is another usage with "lxDummyBackAnnotateMFactorName".

2. lxDummyBackAnnotateMissingTerm

In 'Cadence Help', it says "Allow dummies to be backannotated when the layout instances has missing terminals compared to the schematic".

However, I can't find any differences whether the turn on the setting "lxDummyBackAnnotateMissingTerm" or not.

So, I want to know what situation this setting works.

3. Instance property with dummy

When I execute the "Create dummy with net", then two options are made, "lvsIgnore", "ignore".

I think these options are for ignoring these dummies in LVS, but not clearly understood.

So, I want to know what thess options are for?

Best regards.