Peter --
I will give you an opinion, and perhaps the others will have some opinions,
too. Assuming that your actuals are current as of the "last worked" date,
here's the technique that I might use:
1. Open the cancelled project
2. Click Tools - Tracking - Update Project
3. Select the "Reschedule remaining work to start after" option
4. Set the reschedule date to the "last worked" date
5. Click OK
The above steps will reschedule any uncompleted work from the past into the
next time period after the "last worked" date. Next, complete these steps:
1. Click Project - Filtered for - Incomplete Tasks
2. Click Window - Split
3. In the bottom pane, right-click and select the Resource Work option
4. In the top pane, select an incomplete task
5. In the bottom pane, set the Remaining Work to 0 hours for each resource
6. In the bottom pane, click the OK button and then click the Next button
7. Repeat steps #3-6 for every incomplete task
8. Click Window - Remove Split
9. Save the project
10. Click Collaborate - Publish - All Information
Hope this helps.