1. I added the [ CODE ] tags around your macro for you to format it; you can use the [#] icon to insert the tags and paste your macro between them next time

2. Question: Is this your workflow?

a. Create a presentation and save it as "mypres.pptm" on Monday (1/1/2018)

b. Open it on Tuesday and it saves as "2018-01-02_mypres_v1.pptm"

c. Open it again on Tuesday and it saves as "2018-01-02_mypres_v2.pptm"

d. Open it on Wednesday (1/3/2018) and it saves as
"2018-01-02_mypres_v3.pptm" OR as --- Same date, bump version
"2018-01-03_mypres_v1.pptm" OR as --- New date, restart version
"2018-01-03_mypres_v3.pptm" --- New date, bump version