We are going to use the standard integration of Sales Quotes created in Dynamics Sales with Business Central.

The customer uses comment-type lines in Business Central in quotes.

But we saw that some issue they get, at the moment it is not possible to also integrate these lines in Dynamics Sales.

Currently, there is no synchronization of lines back to Dynamics 365 Sales. In BC Wave 2 2022 it will be, but we will not synch back the comment lines which you are asking for, because there is no such line type in Dynamics 365 Sales salesorder.

You will need to customize the integration and decide what do with BC comment lines (concatenate them and put on the line description of the line above, or something else). It will be up to you what to do with comment lines. There is no off-the-page solution for this, because we cannot know what are the comment lines related to: is it to the line above, or is it just “Thank you” message at the bottom of all the lines.