Response Spectrum Analysis (CQC)

I am doing analysis of a Simple frame by Response Spectrum method in staad.I have only 2 load cases.

I defined EQ Mass in “Definitions” and applied the selfweight and live load in all 3 directions.

I am doing the same analysis in 2 separate staad files.In first file ,I have 2 beams without any nodes in-between.

In file 2, I have 2 beams with nodes in-between which makes it 6 members in staad.

The same Load is applied in both beams and analysed.

In File without any nodes in-between, I am getting Zero Bending moment in My of beam 243 and 235 for Z direction Seismic Load.

In File with nodes in between , I am Getting My moment of 10KNm for the same beam in same load case.

Ques 1: Why am I getting different analysis results for just adding nodes in-between?

2 more questions which are not directly related to the above issue.

Ques 1a: Is there a way to make staad take mass automatically from the load definitions instead of applying manually every time?

Ques 1b: How to make staad magnify dynamic shear by a factor automatically by comparing it with static shear?

P.S : Both Staad Files are attached.