You can now replace the escapement platform. Do not completely tighten the screws.

Visually check that the escapement pinion is fully engaged with the contrate wheel, but not pressing on it, otherwise it will create friction and prevent the clock from running as long as it should. Examine with a magnifying glass.

Tighten the screws and check the escapement platform hasn't moved in doing so. Wind the main spring just a little and make sure the clock runs.

It's critical to ensure both that there is minimal endfloat in the contrate wheel, and that it engages fully but doesn't press on the escapement pinion.