Answer
The registry-based table-alias setup only matters for Crystal Quick Reports specifically — it isn't needed for Crystal operational reports, so you don't need to add it universally for all reports. In a Crystal Quick Report, prefixing a view name with \ or \\ in the layout tells the framework to automatically supply that view's login credentials rather than prompting the user for them at print time — \ signals a schema-owner view and \\ signals an IAL-owner view. Since Crystal itself doesn't natively understand these two alias prefixes, a registry entry is required wherever the alias needs to be resolved: if using IFS Enterprise Explorer together with Crystal Web Service, that registry entry is added automatically by the Crystal Web Service installer on the server it's installed on, and no equivalent entry is needed on the client machine used just for previewing; separately, the machine used to design layouts in Crystal Report Designer itself also needs the corresponding registry entry added (with specifics varying by Designer version, per the vendor documentation) to be able to use \ or \\ aliases while designing. If instead using a Centura client rather than IFS EE, the registry entry needs to be added on each client machine used to preview reports, per the setup documentation for that older client.