This is mostly because the package has been installed directly on the live or dev environment on Umbraco cloud (where changes to web.config is not commited to git) or a merge of Web.Config has removed a setting in the Web.Config file.
To fix this just add this line of code to your handlers section in your Web.config.
<add name="IglooThemeHandler" path="igloo.theme" verb="*" type="Igloo.Resolvers.ThemeResolver, Igloo" resourceType="Unspecified" preCondition="integratedMode" />
Make sure you have Umbraco Forms installed and have no previous installation of Igloo.
Open umbracoSettings.config and remove svg from <disallowedUploadFiles>
To get the map working you first need a Google maps API key. Once you have your key go to the Settings -> General node and paste it in the input under the Advanced tab.
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