Can CircuitWorks Overcoat Pens withstand soldering temperatures?

No. CircuitWorks Overcoat Pens should be the final step in processing the board. The Overcoat material is a modified acrylic conformal coating not an epoxy resist material, so it does not have the same properties of durability and permanence as a permanent solder resist. It will decompose at temperatures above 270°F (132°C), and therefore should only be applied to the board after all soldering has been done. When soldering is required after the repair has been done, Chemtronics offers CircuitWorks Epoxy Overcoat (CW2500). It is a permanent green coating formulated to protect circuit traces before being exposed to reflow conditions. Epoxy Overcoat two component, 100% solids epoxy that is engineered specifically for high temperature resistance, used for electronic circuit and component protection.