Thank you for your questions.
1) The models need to be saved with a new extension. This process takes about 2 minutes and does not effect the functionality at all.
2) V7 has not been supported in 10 years.
Do you have a few minutes free to discuss? I certainly appreciate your concerns about upgrading close to month-end. However, this upgrade will be painless and we can support use in the new environment you have described.
Please feel free to call me directly (978) 275 8315 or send me an email Andrew_baldwin@datawatch.com
I look forward to working with you.