Minor alterations, including load-bearing wall – correct process?

We have an owner who has submitted structural engineering report for some minor alterations they want to do (1 new doorway in non-load-bearing wall and installing of a beam after removal of part of a load-bearing wall).

What is the correct procedure for this?  She has applied via the strata manager by submitting the engineers report and is seeking EC approval.

1) Does she need a DA?  Initial questions to council appear to indicate yes.

2) Do we need a GM to approve this or can the EC approve?  If EC can approve are there communication requirements to adjoining owners?  What is the threshold at which a GM is needed.

3) Is a by-law needed? If not, do we have adequate protection under the strata laws to hold the owner to rectification of any damage or unforeseen consequences of the works.

Side question – can GMs be conducted via Skype conference calls?

Thanks in advance for any advice in this matter.