Marginal entry is linked registration type which indicates particular change for the initial registration. Marginal entry specifies how the change impacts the initial registration: details, reasons, consequences, etc.
To register marginal entry, linked registration record (of initial registration) must be added (1.3 Add linked registrations). When linked registration record is added, you can mark it as marginal entry (Figure 82 - Figure 85):

Figure 82 Mark linked registration as marginal entry

Figure 83 Entering marginal entry information

Figure 84 Added marginal entry
Initial registration record can be opened and reviewed (Figure 85).

Figure 85 Initial registration record