update readme

README.md

@@ -53,7 +53,7 @@ Contributions welcome - please refer to [CONTRIBUTING.MD](https://github.com/sem
 [![PyPI version](https://img.shields.io/pypi/v/pyspartn)](https://pypi.org/project/pyspartn/)
 ![PyPI downloads](https://img.shields.io/pypi/dm/pyspartn.svg?style=flat)
 
-`pyspartn` is compatible with Python 3.9 - 3.13*¹*.
+`pyspartn` is compatible with Python 3.9 - 3.13. It utilises the Python `cryptography` package to decrypt SPARTN message payloads*¹*.
 
 In the following, `python3` & `pip` refer to the Python 3 executables. You may need to substitute `python` for `python3`, depending on your particular environment (*on Windows it's generally `python`*). **It is strongly recommended that** the Python 3 binaries (\Scripts or /bin) and site_packages directories are included in your PATH (*most standard Python 3 installation packages will do this automatically if you select the 'Add to PATH' option during installation*).
 
@@ -74,7 +74,7 @@ python3 -m pip install --upgrade pyspartn
 deactivate
 ```
 
-*¹* On some 32-bit Linux platforms (e.g. Raspberry Pi OS 32), it may be necessary to [install Rust compiler support](https://www.rust-lang.org/tools/install) in order to install the `cryptography` library which `pyspartn` depends on to decrypt SPARTN messages. See [cryptography install README](https://github.com/semuconsulting/pyspartn/blob/main/cryptography_installation/README.md).
+*¹* On some 32-bit Linux platforms (e.g. Raspberry Pi OS 32), it may be necessary to [install Rust compiler support](https://www.rust-lang.org/tools/install) in order to install the `cryptography` package which `pyspartn` depends on to decrypt SPARTN message payloads. See [cryptography install README](https://github.com/semuconsulting/pyspartn/blob/main/cryptography_installation/README.md).
 
 For [Conda](https://docs.conda.io/en/latest/) users, `pyspartn` is also available from [conda-forge](https://github.com/conda-forge/pyspartn-feedstock):