@Wang, Jane Firstly, apologies for the delay in responding here and any inconvenience this issue may have caused.
"SIG does not directly support software installs and patches. VM applications (coming soon) - will allow customers to do software installs."
Shared gallery images are very specific to VM images. You can still manage their software patches and other software repositories using shared gallery images - by versioning and grouping the images, only thing it just won't be a simply software update instead the entire image would be updated. If it is Windows VM can utilize auto update feature, anything other than windows patches, they will have to build it as an image
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Hope this helps!
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