Issues with Updating Actual Cost and Hours

Using P6 for an enginering firm. We cost and resource load schedules with a blended unit rate to avoid inputing resouces by rate category or an individuals name. We believe this method gives us the level of reporting we need to manage the project from a schedule perspective since we have other systems to report in greater detail. I understand that P6 is set up to calculate cost based on hours x unit rate, but because we are using a blended rate, we need to enter actual period cost, period hours and cost todate for each resource.

Experiencing two problems: