As you said, you installed the 32-bit Notes multi-user installation. Since your project required a 32-bit single-user installation, you ran NICE64-bit again.
If you are running 32Bit installer of Notes client then you need to use the 32Bit Nice tool.
Just download the install package for Admin/.Designer (notes is included), this package in fully Single user installation compared to the Notes package installation.
On setup just do not install admin nor designer, only notes client and you are all set.