Getting data from C-ISAM Informix file

I need to get a customer's data out of a C-ISAM database, and whoever programmed the risc box, left all kinds of Informix fragments. I found the license for online as well as a ton of old levels of data and executables dating back to 1993. I had been trying to get to some old data that the client is still using. After trying to connect through a network using the SDK, I found that the environment was set up wrong. I tried to run dbaccess, but it tells me that the INFORMIXDIR is invalid. I found a program to set up the environment, but it tells me that all permissions, etc will be changed if I run the program. I don't want to damage the accessibility of the files still in use. Is there any way to export the data from the C-ISAM files, or is there a non-invasive way to connect to the database(s). I am new to Informix, but have approximately 18 years of programming experience. Any insight you might provide would be appreciated TIA Alex