Hi @Andries1
To summarize the issues / resolutions:
1. The dreaded "InvalidTemplate. Unable to process template language expressions in action" error
Resolved: Export and reimport the Flow as per: Fix the “InvalidTemplate. Unable to process template language expressions in action” error in Power Automate
2. Encodian 'Convert to PDF' action: The action requires the file extension to determine the file type
Resolved: Pass the file name with extension property
3. The SharePoint 'Add to Attachment' action failed due to an incorrect ID (400) error
Resolved: Pass the correct ID
HTH
Jay
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