Release : 10.4.1
Component : Spectrum Core / SpectroSERVER
Not enough memory allocated to the client.
You will need to either reduce the size of the window using the Zoom option, or allocate more memory to the OneClick client. To allocate more memory to the OneClick client, download the OneClick.jnlp to a machine that has enough memory for the allocation. Edit the OneClick.jnlp and change the max heap size to a much larger value, such as 8GB (8192M):
<j2se version="1.8.0_232" java-vm-args="--add-modules=java.se.ee" href="http://java.sun.com/products/autodl/j2se"
Launch this edited OneClick.jnlp and you will then be able to export the topology (if you still received the out of memory error, you will need to allocate more memory).