32-bit applications, like Bryce, can officially only manage 2 GB of memory. However, it can actually manage 4 GB, 2 of them are reserved for the operating system (Windows). There is a means to get some of those reserved 2 GB back for the running application. Most 32-bit programs have a flag that can be set to take some of those reserved 2 GB for them, and Bryce can be made Large Address Aware (LAA). There is a free program that can be downloaded and just unpacked into any folder on your disk (around 40 KB - kilo, not mega or giga). When Bryce is set to LAA, it can use around 3.2 to 3.5 GB of memory, provided your machine has at least 4 GB of memory. I use LAA not only for all my installed Bryce (4 to 7.1) but other programs, too on my Win 7 and Win 10 computers.
You may watch this video (link below), in which I explain how to get the tool and use it.

https://www.youtube.com/watch?v=UDZmETVO15c