The NAND and NOR blocks are problems for the automatic conversion process. So you need to convert those to the equivalent circuit. In your case the NOR blocks are converted.

Figure 1: NOR to AND with NOT

The original circuit looked something like:

Figure 2: Approximated original FBD circuit

The swapped out blocks may look something in the style of:

Figure 3: Approximated modified FBD circuit

The LAD conversion may then have the style:

Figure 4: Approximated LAD circuit