We're currently running our game using legacy custom servers, and bundling dependencies (ie. required DLLs) with the uploaded package. In particular, we know the game requires at least Direct X and C++ runtime libraries -- if these are not packaged with the game, the application fails to launch with a corresponding error message indicating the missing DLL(s).
Rather than packaging the DLLs with the upload archive, we've also tried using a bootstrap script to run redistributable installers, instead. However, this always fails: the redistributable applications routinely prompt for user input, even when using appropriate command-line switches as documented for each, respectively; at the very least, both must be run with administrative privileges, which results in a prompt for credentials. We do not know what credentials would be valid, or even what usernames would be valid, when constructing such scripts.
Using the Thunderbird service, it is also not clear how we would provide a custom image for the server host virtual machines -- or if this is even possible.
TL;DR
1. What is the recommended way to install dependencies onto custom server hosts using the legacy service? If necessary, would you be able to provide user names and credentials which could be used by our scripts to facilitate calling redistributable package installers with elevated privileges where required?
2. Would use of the Thunderbird service be preferable w/ respect to our having to install redistributable packages? If so, what would be the procedure?
If neither of the above are reasonable (ie. the prefered/best approach is simply to continue packaging the required DLLs along with the build archive), it would be helpful to have that confirmed, too. Ultimately, we know that this approach works, so if it is the best available, that's just as well.
Thank you in advance for reading all this, and hope to hear back.