Save and Load Redmark File
All relevant files should be saved together into same folder.
Example:
Path: C:\Temp\Altair-PollEx\PollEx_PCB\Redmark+
Project Name: Project1
Redmark+ File Name: Project1.prmkp
C:\Temp\Altair-PollEx\PollEx_PCB\Redmark+\Project1\Project1.prmkp

Figure 1.
You can load the file (*.prmkp) which has same name with the project folder. Select top-level folder to open it.

Figure 2.