Background:
I am running office 365 and am working on an excel worksheet on a Microsoft Surface Go 2 tablet. I want to use a worksheet, daily, to record certain data (e.g., temperature). Each day, once the data is entered, the user will initial beside the data they have entered (using the draw function).

To ensure data/signatures are not modified after entry, using a macro, excel locks cells containing data/signatures and password protects the worksheet. Blank cells, which will be used for future data/signature entry, remain unlocked.

Issue: Although data can subsequently be entered into unlocked cells, users cannot initial beside the data they have entered. From what I can tell, excel blocks drawing on a protected worksheet.

Questions:
  1. Can drawing be enabled on a protected worksheet?
  2. With respect to a protected worksheet, why would drawing disabled on unlocked cells? Is this a bug, or a feature?

When protecting the worksheet, I can allow the user to edit objects. This will allow them to sign beside data they have entered. However, it would also give them the ability to delete previous signatures (which would defeat the purpose of the signature).
Thanks for any help!