Hello,
 
Thank you for reaching out to us.
 
I will address your questions as following:
 

• We do not offer such an option at the moment for the Signature feature, nor the possibility of implementing a validation tool for the Signature field. But we will most definitely take your suggestion into consideration for future improvements.

 

• Unfortunately, it would not be possible to send an application before submitting it. As an alternative, you can send the submission via email for Approval, in which case the submission can be reviewed before accepting it. Keep in mind, however, that as a security measure, the signature will not be visible on the approvals link, but the person who approves it can sign it.

 
I hope this helps. Don’t hesitate to ask if there’s anything you need.