French to English Law/Patents Law: Contract(s)

I would use waiver for "tolérance",and constituent for "constitutive" but I really am wondering if there is a set way to say this phrase. This is the last sentence in a contract between a ship builder and a dealership. I would really appreciate help with the entire sentence. The French is:

Aucune tolérance relative à l'application des clauses et conditions des présentes ne pourra, quelle qu'ait pu en être la durée ou la fréquence, être considérée comme constitutive d'une modification ou novation.

Here is how I have translated it:

No waiver relating to enforcement and conditions of the clauses herein, regardless to length or frequency, can be considered as constituent for modification or renewal.

Thank you in advance. Gayle