As recommended in the ACI 435R95 report (section 4.3.3),CSI Software has reduced the default modulus-of-rupture value from 7.5√f 'c to 4√f 'c. This change has been documented as Incident # 19168 in the CSI Release Notes of SAFE Version 12.3.0, Release Date 2010-07-12.
Through manual overwrite by checking radio button of User Specified, users are welcome to comply with the previous 7.5√f 'c value, or apply another value based on engineering judgment or project requirements. This is done by selecting Define > Materials... > Modify/Show Material... as shown in Figure 1:
For British, Hong Kong, Indian and Singapore Standards, program default modulus of rupture for cracked deflection is limited to 1 MPa or 0.55 MPa in short term and in long term deflection calculations, respectively. Those limits can be overwritten based on your engineering judgment by entering any other value under User Specified.