I have earlier made clear that the visualized principal image of Cintāmaṇi in the visualization protocol of the Ippokai soriya-hō 一法界法 （Secrets of Rishukyō-bō 理趣経法）, was Mikan hōju 密観宝珠, which attracted attention in research on medieval hōju and was regarded as the principal image of the Nyoirin-Kannonhō 如意輪観音法.
Furthermore, from the standpoint of understanding that the Rishukyō-bō is the Hōju-hō 宝珠法, it was found that there was a case of secretly reading the Rishu-kyō （Adhyardhaśatikā prajñāpāramitā） during the Goshichinichi no mishi-hō 後七日御修法.
As this principal image had the character of being a symbol of Mahāvairocana of the non-duality of the Vajradhātu and Garbhadhātu, it was later adopted as the central object of worship when Kōshin 弘真 established the Sanzon Gōgyō-hō 三尊合行法.
The Sanzon Gōgyō-hō is even said to be among the achievements of Cintāmaṇi worship, and the shape of the Cintāmaṇi, which was established as the principal image of the Ippokai soriya-hō and likely influenced the Sanzon Gōgyō-hō, is pointed out.
Therefore, I think that the existence of the Rishukyō-bō as a Hōju-hō called Ippokai soriya-hō can be added as a topic of Cintāmaṇi worship.
