Thanks for the files. Could you downgrade to the non beta version here, please? The error is related to the header image not being loaded. Could you try activating the option under PDF Invoices > Advanced > “Embed images” as well, please?
Since we haven’t heard from you in a while, I will mark this topic as resolved. Feel free to reopen it if you still need more help, or open another thread if you need help with something else.