We have a rough idea of how this will work, although the details are still being sorted out as we create the technology :
In an ERC-20, all of the tokens are created at once and sold to investors. For ZooBC, there will be no tokens at the beginning of the network. All tokens will be created from blocks that are created by nodes and distributed to people in the ZooBC node registry.
Therefore it is impossible for us to sell the tokens before the network launches, and we have no plans to do an ICO. Instead, we will sell spots in the node registry to initial investors. If the investors run the nodes correctly, they will generate a lot of new tokens from creating blocks. The rate at which other people can join the registry is limited by the Proof of Participation algorithm. Therefore these early spots in the registry are quite valuable to generate the first coins on the network.
After the network has been operating for some time, we will attempt to add it to exchanges so that people can buy coins normally.
So, in summary: to invest in the ZooBC network before the launch, you must buy a seat in the node registry. When the network starts running, your node can generate you a lot of coins. And when the coins take on the value in an exchange, you can freely sell them on the market, or HODL as you like.