Region mapping broken in CF template
First of all: providing a PAYG option of PowerCenter is a good idea. So it would have been nice, if the installation worked.
Unfortunately the Cloud Formation template on which the PowerCenter stack is based does not contain a region mapping for AMI images with RHEL. This means that after you selected PowerCenter 10.2 on RHEL and set all the configuration options the following error message appears:
"Template validation error: Template error: Unable to get mapping for AWSAMIRegionMap::us-east-1::INFORMATICAPCRHELHVM"
When looking into the code of the cloud formation template it becomes obvious that that the region mapping only covers the windows AMIs.