Well, you could start here: <a href="https://wiki.roll20.net/Solving_Technical_Issues" rel="nofollow">https://wiki.roll20.net/Solving_Technical_Issues</a> Depending on the age/grade of your hardware and the quality of your internet connection, you may have trouble loading larger maps, especially with dynamic lighting enabled. The larger the map, the more dynamic lighting lines there are, the more tokens there are that have vision or shed light that need rendered, and so on all add up. I have one player in a game that can't load a dynamically lit map if the base image is much over 2MB, so that may or may not be a similar issue for you. Whoever is running the game might want to look at the following articles. <a href="https://wiki.roll20.net/Optimizing_Roll20_Performance" rel="nofollow">https://wiki.roll20.net/Optimizing_Roll20_Performance</a> <a href="https://wiki.roll20.net/Dynamic_Lighting_Examples#Best_Performance_Guide" rel="nofollow">https://wiki.roll20.net/Dynamic_Lighting_Examples#Best_Performance_Guide</a> <a href="https://wiki.roll20.net/Best_Practices_for_Files_on_Roll20" rel="nofollow">https://wiki.roll20.net/Best_Practices_for_Files_on_Roll20</a>