It might be indexed fields but that is a two edged sword. Filemaker can find and sort much more quickly with indexed fields but when you connect remotely each index in downloaded as a whole even if you are not viewing that field. Portals with conditional views. Script triggers that perform sorts on multiple fields can all slow things down. While tiresome you should start with simple layouts and add your elements and then test. Same with scripts that run automatically. With 500 records it should be fairly quick but nowhere near as fast as with a local connection.