Executing a TAB (next cell) command from within a merge

For the first question, at the point in the If...then...Else field construction where you want the feature to be used, you simply press the relevant key on the keyboard.

As an example:

{ IF { MERGEFIELD Address2 } <> "" "{ MERGEFIELD Address2 }¶

{ MERGEFIELD City }" "{ MERGEFIELD City }" }

In the above you would press the Enter key where the ¶ appears and, if the Address2 field is not empty, the data from that field will be inserted followed by a paragraph return and the data from the City field will appear on the next line.  If however the Address2 field is blank, then the data from City field will appear on the line following the previous field.

For the second question, the answer is No, but it is possible to use Visual Basic to create a "roll-your-own" equivalent to mail merge and in that way, you can do just about anything.

Examples of this are contained in my MergeTools – 20130627 Add-in that you can download from the following page of my Windows Live SkyDrive:

https://skydrive.live.com/?cid=5aedcb43615e886b#!/?cid=5AEDCB43615E886B!cid=5AEDCB43615E886B&id=5AEDCB43615E886B%21566

It contains facilities to perform the following types of "merge:

Many to One

Merge with Charts

Duplex Merge

Merge with FormFields

Merge with Attachments

Merge to Individual Documents

Merge, Print and Staple

none of which can be performed by Mail Merge out-of-the-box.

While you can include a tab, line break, Enter, or New page as one or the other of the results of an If...then...Else, field construction, if that field construction is located in the cell of the table, the effect of the action will be contained within that cell.  Specifically in the case of a TAB, it will NOT result in the next cell action, but will be treated as if Ctrl+tab was used within a cell.