I currently have a magento 1.9 store running on domain1.ac.uk without any issues.
I'm not getting everything ready for shop.domain2.ac.uk to display different themes and products but work via the same magento admin.
I've created a CMS page unique for shop.domain2.ac.uk. Setup via Manage Stores a new Webiste Name/Store Name and Store View Name for both domain1.ac.uk and shop.domain2.ac.uk
Updated the configuration for shop.domain2.ac.uk to have the correct base url
Added the following code to my index.php
case 'shop.domain2.ac.uk ':
$mageRunCode = 'bpslw';
$mageRunType = 'bpsl';
After this setup, if I go to shop.domain2.ac.uk it gives me a 404 page.
I've found questions like the following: Magento Multi-Store with Domain Alias - 404 Error on 2nd Store
However looking over the answers here hasn't helped as the CMS page for shop.domain2.ac.uk is set to display on all store views.