This release updates the default URLs for Opayo (now owned by Elevon, previously SagePay, and before that Protx). For reference, these should be:
https://sandbox.opayo.eu.elavon.com/gateway/service/vspform-register.vsp
https://live.opayo.eu.elavon.com/gateway/service/vspform-register.vsp
Also, we have revised the Worldpay DLL to include MD5 hashing. This was in response to some clients reporting that Worldpay had contacting them about their installation ID being "compromised". Further investigation suggests that it does not pose any direct threat to the client installation, rather a third party miscreant is using the installation ID to send transactions to Worldpay in order simply to determine which credit cards work or don't work. To prevent this happening, we have added an MD5 hashed value to the form, and this also needs to be setup at the Worldpay side. There are full instructions here:
https://kartris.tome.host/tc/15219