I had similar problems with your points 2, 3, 4
This is how I solved them and now my exported excel file looks perfect.
1 - All fields in the ragic sheet are properly formatted (number with decimal points, text, etc)
2 - I run a first merge to see what goes wrong.
3 - I edit the excel merge template:
a) Formatting all cells with the right text formatting (font, size, etc)
b) I set all merged cells to the “General” type, not to any type of number formatting. If all fields are properly formatted in ragic, excel will merge with their values as they show in ragic… no dots or anything added. By doing this not only they show properly but numeric fields can be further processed in excel if you need to do so.
The only exception to this are cells date fields, that you may need to format in excel to meet your specific date formatting (in my case dd-MMM-yyyy).
c) I format then all the page settings of the excel sheet: margins, no cell lines, headers, print area , etc
d) finally upload the fully formatted template to ragic