Where to find SerumFX?
SerumFX is a bonus plugin available to customers. You can download it from your account/Serum page.
In the case of Splice rent-to-own, it is available once payments begin (after the 3-day trial period). You can find it on Splice under https://splice.com/plugins/your-plugins. See their support page on this topic.
Alternatively, you could use "forgot your password" on the Sign-in page on this website to the email you started the lease under (the email you use for your Splice account) - once logged in, you will find SerumFX in "your account".