I'd be happy to help you with installing the software and providing more information about Helium Music Manager.

Based on the key you provided, `instal the last version for iPhoneHelium Music Manager Premium 16.4.18312`, it seems like you're looking to install the latest premium version of Helium Music Manager for iOS (iPhone).

Here's a step-by-step guide to help you get started:

1. Install the software: Download and install Helium Music Manager from the official website or other trusted sources.

2. Launch the app: Once installed, launch the app on your iPhone.

3. Unlock Premium: On the app's main interface, click 'Get Premium Version' and then 'Unlock Premium'.

4. Enter license key: Note that the giveaway license key only works with version 4.0, so make sure you don't upgrade to a later version.

As for system requirements, Helium Music Manager can be used on computers running Windows 11 or Windows 10. Previous versions of the OS, such as Windows 8 and Windows 7, should also work fine.

Here are some additional features of Helium Music Manager:

* Make and take phone calls on cellular networks

* View your photo gallery (up to your most recent 2,000 pictures and screenshots)

* Write and reply to SMS text messages, send photos, emojis, GIFs, and media content

Regarding the PC software, the latest version available is Helium Music Manager 16.4.

If you're looking for more information on Helium Streamer or Music Finder File Manager, please let me know!

Also, I noticed that you mentioned MuseScore as another program. If you'd like to learn more about it, including downloading the source files and building it for your OS, I can provide you with some resources.

Lastly, regarding the file size of Helium Music Manager 2 Premium Multilingual, it's approximately 38 MB.

Please let me know if there's anything else I can assist you with!

Instal the last version for iphoneHelium Music Manager Premium 16.4.18312