Update unsupported providers list

modules/ROOT/pages/ForUsers/DedicatedServerSetup.adoc

@@ -58,7 +58,14 @@ We do not currently maintain a list of server hosts that support modded servers.
 The following 3rd party hosting services are known to **NOT support mods**,
 regardless of what their websites and marketing pages claim:
 
-- low.ms
+// cspell:ignore nitroserv gportal
+
+- low.ms - Does not allow executables
+- nitroserv.games - Allows creating but not deleting dot files, which bricks the server
+- Shockbyte - Doesn't show the root executable
+- gportal - Doesn't show the proper game file tree, just the Saved folder
+
+It is also worth noting that AMP causes SFTP to throw weird errors, but mods can be installed if pointing SMM to a network mount or local path as described link:#FileTransferMethods_SMB[here].
 
 If you believe a site is listed here in error,
 contact us about it on the https://discord.ficsit.app[Discord].