I have remounted the acrylic side windows twice on my 33 Hunter. I'm not sure how similar this is to the windows on your 19, but here's what I have found.
1 - I have a 2015 33, and in 2016 I started seeing leakage on several of the side windows. I have good business contacts with Marlow-Hunter, and here is what I found from them:
2 - Before 2016 (approx) they had used Dow-Corning 795. This had been originally used on my 2015 33.
3 - As of 2016 Hunter changed to Sika Adhesive/Sealant 295-UV, which also needs Sika Primer 209D. I used this to repair the windows. They were kind enough to send me a Hunters SOP, and I did use the screws that were with the original windows when re-mounting them. (Sorry but the SOP document was too large to attach.)
4 - Just 3 years later, in August 2019 my side windows were again leaking. I contacted my Quality contact at Marlow-Hunter, found they had changed again. Now their preference was 3M 4000UV Black. This time I suspected leakage may be from the screws. After looking into several Forums, I decided to stay with the Sika 295-UV, because I had not seen much about the 3M 4000UV in forums. One big change I made was to re-mount the windows WITHOUT the screws. Several good forums discussed options of not using the screws.
5 - So far it's one year later, and we're going through the rainy season in Florida. I have not seen any leakage.
