17025: 2017 differences

You asked

I need to know if there are any differences between the FINAL DRAFT version and the one that was actually issued?

Please note that both the Final Draft International Standard (FDIS) and the final published document are copyright protected. The FDIS is circulated to all ISO members for an 8 week  vote,  For more details on the ISO various stages to publication, see  https://www.iso.org/stages-and-resources-for-standards-development.html
I cannot provide a comparison. Although you will see ISO state that “Only editorial corrections are made to the final text”, these corrections can have a significant impact on the interpretation and required implementation steps for the laboratory. ISO state that from FDIS to Publication stage, the project leaders may submit comments on the FDIS. Then the committee managers and project leaders get a two-week sign off period before the standard is published.

You also asked

So if someone uses the final draft as guidance, are there any changes that they can be held to?

ISO 17025:2017 requires the laboratory to have

• the available resources necessary to manage and perform its laboratory activities (Clause 6.1)
• relevant versions of all applicable documents  to be available at points of use.

This will clearly include the need to have the latest version of ISO 17025:2017. 
For further information on ISO 17025 requirements, see the following:

The whitepaper Clause-by-clause explanation of ISO 17025:2017 at https://info.advisera.com/17025academy/free-download/clause-by-clause-explanation-of-iso-17025/
The ISO 17025 toolkit at https://advisera.com/17025academy/iso-17025-documentation-toolkit/