Convert attributes to/from multiline attributes, updating existing inserts.
Keyboard Command: BlkAttMul

Procedure:
- Open the drawing containing the block inserts.
- Initiate this tool.
- Select the Blocks to process on the list on the left.
- Select the attributes to process on the lists on the right.
- Choose the button to begin.
Notes:
- If a tag is selected in the Single Line Tags section, it becomes a Multiline attribute.
- If a tag is selected in the Multi Line Tags section, it becomes a single line (standard) attribute.